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Finding the Fourth Proportional to 391.05, 539.03 and 308.01

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Solution

The fourth proportional to 391.05, 539.03 and 308.01 is: 424.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.05 : 539.03 = 308.01 : x
  2. Step 2: Convert to fraction form
    391.05/539.03 = 308.01/x
  3. Step 3: Cross multiply
    391.05x = 539.03 × 308.01
  4. Step 4: Simplify right side
    391.05x = 166,029.42
  5. Step 5: Solve for x
    x = 166,029.42/391.05
  6. Step 6: Final answer
    x = 424.57

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.